Minimally Invasive Surgery

Emerging trends

Davide Lomanto

Director,
Minimally Invasive
Surgical Centre (MISC),
NUH, Singapore

Technological innovations in the field of robotics, and telemedicine will drive the future of minimally invasive surgery.

The substantial developments in surgery, over the last century with the advent of antiseptic substance, anaesthetic agents, antibiotics, surgical nutrition, and organ transplantation, did not modify the basic tools of surgery and even the surgical techniques remained basically unchanged.

But in the last few decades, “invasiveness” has been the focus of surgical practice gaining the momentum especially because of the better outcome in terms of post-operative pain, fewer complications and quicker return to functional activity. The change was initiated with the advent of the laparoscopic surgery, and because of the rapid acceptance and success of such operations as laparoscopic cholecystectomy, over the last two decades a revolution has taken place in general surgery. Since then, a variety of surgical operations in the entire surgical speciality have used endo/laparoscopic techniques.

Image 1 The modern era of laparoscopic surgery ushered in when a miniature video camera was attached to the eyepiece of the laparoscope, which allowed multiple observers to view an operative field from the same vantage point. But the major push happened when many large series were reported in the literature highlighting main advantages of the laparoscopic approach over traditional “open” surgery (in terms of reduced postoperative pain, shorter hospital stays, periods of disability and cost-effective for hospitals and patients).

The media quickly portrayed laparoscopic surgery, with its small incisions, as a panacea, inventing different name as “key-hole surgery”, “minimally invasive”, “band-aid” or “Nintendo surgery” (Image-1). Hence, the success among patients was great which helped in the growth of minimal invasive surgery supported by the development of new high-tech instrumentation and devices.

The evolution

Image 2 During the initial years, laparoscopic surgery was limited by a number of factors such as: two-dimensional vision, the control of the surgical field by an assistant. The laparoscopic port, restricted the freedom of movement of the instruments which themselves were straight without articulated movements like human wrist. Moreover, the instruments utilized, did not provide any tactile or force feedback. Nevertheless, the number of operations grew, surgeons became skilled over the limitation imposed by laparoscopy and along the years this gap was almost recovered. The new high-technology equipment not only resulted in changes to Hospital design — as OTs had to be redrawn according to the new devices — but the surgical training programmes also had to be re-organised. Together with technological development new approaches come-out.

The size of ports used to access the abdominal cavity decreased over time from 10 mm to 2 mm. The 2-mm ports, called “needlescopic” ports, have proven to be feasible, safe, and effective when an enlarged port is not required for extraction of a specimen. Benefits include less postoperative pain and improved wound cosmesis. The use of “hand-assisted” ports, in which a hand is inserted into the peritoneum to assist the performance of the surgical procedure, allows for tactile assessment by the surgeon. This different surgical approach is particularly advantageous when a larger incision is needed to remove the surgical specimen like donor nephrectomy, splenectomy or gastric surgery or for cases that are too complex or take too long to be managed with the total laparoscopic technique. The application of the minimally invasive procedure to more complex surgeries will require new technology and techniques. In general surgery, techniques such as hand-assisted laparoscopy attempt to bridge the gap between open and completely endoscopic procedures. Other possibilities include developing new ways to perform conventional surgical tasks as a way to adapt these procedures to an endoscopic or less invasive surgical approach.

Image 3 Inanimate trainers (Image-2) or simulators (Image-3) are being used as teaching tools to improve surgeon performance, and the use of self-retaining retractors has enabled the surgeon to use fewer assistants in the operating room. More recently, robot-assisted surgery has emerged as a popular method. Robotic arms allow the surgeons for finer control and remote presence and provide a computerized interface between the patient and the surgeon. The DaVinci Robotic system (Intuitive Surgical, USA), provides enhanced dexterity, motion scaling, articulation, 3-dimensional vision and the potential for telesurgery. However, the number of surgical applications of robot-assisted surgery are increasing slowly, mainly due to the high investment and running costs of the devices even though the initial benefits exist. But new applications must be developed as the full range of robotic application is still to be implemented. The initial concept of robotics in surgery involved operating at a remote site from the surgeon. The ability to transpose surgical and technical expertise from one site to a distant site (i.e.: proctorship, assisting developing country or remote area like) was thought to expand surgical application. Although simple surgical procedures have been performed remotely, there are some difficulties for an extensive clinical use because of high costs, transmission delay and medical and legal issues.

The future

Application of telepresence surgery in the foreseeable future will probably be limited to telementoring rather than to remote manipulation. Telementoring will allow the surgeon to teach or proctor performance of an advanced or new technique at a remote site using real-time teleobservation and monitoring. New broadcasting technologies such as high-speed broadband telecasting - a technology that allows the users to utilize non-compressed audiovisual signals keeping high quality, low delay (Image-4) that are now in the early stages will soon be available worldwide. However, a robotic development in the area of software simulation and virtual reality could be expected. Also surgical operations and that need dexterity enhancement and motion microscaling will need robotic assistance.

Image 4 Other possible roles for computer and robotic assistance in surgery include voice control over surgical manipulators and information manipulators. At present, technology exists to give the surgeon voice control over virtually all operating room equipment including electrocautery, operating table position, laparoscopic movement-control, lighting and telephone. Future developments promise the overlay of additional data to the operative field including 3-dimensional magnetic resonance imaging reconstructions and physiologic data acquisition, especially for pre-operative virtual simulation.

In conclusion, efforts are now focussed on those techniques that facilitate more complex tasks by the minimally invasive approach. Other aspects are the clear role of audio-visual telementoring in future training concepts and of telemanipulation/telesurgery. New technological concepts promote the development of hand-held mechanical manipulators used in combination with mono-tasking computerized robots like AESOP, resulting in a significant cost reduction. Advancements in microchip and wireless technology may allow the development of microrobots for completing surgical procedures and magnetically controlled implants that can be navigated remotely.

The technological innovations in surgery are only beginning, the future will be very attractive, the potential is enormous and the path is minimal.